Event Driven Development

Transcript

1. Event Driven Development
   Christopher Riley
   ConFoo 2018
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2. Introduction
   

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3. Introduction
   • Event sourcing
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4. Introduction
   • Event sourcing
   • Event Driven Architecture
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5. Introduction
   • Event sourcing
   • Event Driven Architecture
   • Task Based UI
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6. Introduction
   • Event sourcing
   • Event Driven Architecture
   • Task Based UI
   • Event storming
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7. What is an event?
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8. What is an event?
   • Something which has happened in the past
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9. What is an event?
   • Something which has happened in the past
   • Relevant to a domain expert
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10. What is an event?
    • Something which has happened in the past
    • Relevant to a domain expert
    • Not technical
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11. What is an event?
    • Something which has happened in the past
    • Relevant to a domain expert
    • Not technical
    • Raised in response to an input
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12. Task based UI
    

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13. A CRUD UI
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14. A Task Based UI
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15. Everything a company does is part of a
    process
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16. Why are task based UI’s helpful to event
    based systems?
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17. Event sourcing
    

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18. A familiar model
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19. Event sourcing example
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20. What does an event sourced system actually
    look like?
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21. Event sourcing architecture
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22. Handling a command
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23. Inside the model
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24. Inside the model
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25. Handling Events
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26. Projections
    

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27. Projections
    • Turn events into read models
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28. Projections
    • Turn events into read models
    • Can be eventually consistent
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29. Projections
    • Turn events into read models
    • Can be eventually consistent
    • Can be rebuilt
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30. A projection
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31. Process Managers
    

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32. Process managers
    • Handle business logic around events
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33. Process managers
    • Handle business logic around events
    • A state machine
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34. Process managers
    • Handle business logic around events
    • A state machine
    • Keep track of failures
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35. Process managers
    • Handle business logic around events
    • A state machine
    • Keep track of failures
    • Be careful with replays
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36. A Process Manager
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37. Event Driven Architecture
    

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38. Event Driven Architecture
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39. Cross System Process
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40. Conclusions
    

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41. Thanks
    • @giveupalready
    • https://github.com/carnage
    • https://carnage.github.io
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